3.5 Withdrawal of priority claim 

Applicants may voluntarily withdraw a claimed priority at any time. If they do so before the technical preparations for publication have been completed, then the priority date is not effective and the publication is deferred until 18 months after the filing date. If it is withdrawn after the technical preparations for publication have been completed, then the application is still published 18 months after the priority date originally claimed (see A‑VI, 1.1 and G‑IV, 5.1.1).